136 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			136 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | // Formatting library for C++ - std::ostream support
 | ||
|  | //
 | ||
|  | // Copyright (c) 2012 - present, Victor Zverovich
 | ||
|  | // All rights reserved.
 | ||
|  | //
 | ||
|  | // For the license information refer to format.h.
 | ||
|  | 
 | ||
|  | #ifndef FMT_OSTREAM_H_
 | ||
|  | #define FMT_OSTREAM_H_
 | ||
|  | 
 | ||
|  | #include <ostream>
 | ||
|  | 
 | ||
|  | #include "format.h"
 | ||
|  | 
 | ||
|  | FMT_BEGIN_NAMESPACE | ||
|  | 
 | ||
|  | template <typename OutputIt, typename Char> class basic_printf_context; | ||
|  | 
 | ||
|  | namespace detail { | ||
|  | 
 | ||
|  | // Checks if T has a user-defined operator<<.
 | ||
|  | template <typename T, typename Char, typename Enable = void> | ||
|  | class is_streamable { | ||
|  |  private: | ||
|  |   template <typename U> | ||
|  |   static auto test(int) | ||
|  |       -> bool_constant<sizeof(std::declval<std::basic_ostream<Char>&>() | ||
|  |                               << std::declval<U>()) != 0>; | ||
|  | 
 | ||
|  |   template <typename> static auto test(...) -> std::false_type; | ||
|  | 
 | ||
|  |   using result = decltype(test<T>(0)); | ||
|  | 
 | ||
|  |  public: | ||
|  |   is_streamable() = default; | ||
|  | 
 | ||
|  |   static const bool value = result::value; | ||
|  | }; | ||
|  | 
 | ||
|  | // Formatting of built-in types and arrays is intentionally disabled because
 | ||
|  | // it's handled by standard (non-ostream) formatters.
 | ||
|  | template <typename T, typename Char> | ||
|  | struct is_streamable< | ||
|  |     T, Char, | ||
|  |     enable_if_t< | ||
|  |         std::is_arithmetic<T>::value || std::is_array<T>::value || | ||
|  |         std::is_pointer<T>::value || std::is_same<T, char8_type>::value || | ||
|  |         std::is_same<T, std::basic_string<Char>>::value || | ||
|  |         std::is_same<T, std_string_view<Char>>::value || | ||
|  |         (std::is_convertible<T, int>::value && !std::is_enum<T>::value)>> | ||
|  |     : std::false_type {}; | ||
|  | 
 | ||
|  | // Write the content of buf to os.
 | ||
|  | // It is a separate function rather than a part of vprint to simplify testing.
 | ||
|  | template <typename Char> | ||
|  | void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) { | ||
|  |   const Char* buf_data = buf.data(); | ||
|  |   using unsigned_streamsize = std::make_unsigned<std::streamsize>::type; | ||
|  |   unsigned_streamsize size = buf.size(); | ||
|  |   unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>()); | ||
|  |   do { | ||
|  |     unsigned_streamsize n = size <= max_size ? size : max_size; | ||
|  |     os.write(buf_data, static_cast<std::streamsize>(n)); | ||
|  |     buf_data += n; | ||
|  |     size -= n; | ||
|  |   } while (size != 0); | ||
|  | } | ||
|  | 
 | ||
|  | template <typename Char, typename T> | ||
|  | void format_value(buffer<Char>& buf, const T& value, | ||
|  |                   locale_ref loc = locale_ref()) { | ||
|  |   auto&& format_buf = formatbuf<std::basic_streambuf<Char>>(buf); | ||
|  |   auto&& output = std::basic_ostream<Char>(&format_buf); | ||
|  | #if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
 | ||
|  |   if (loc) output.imbue(loc.get<std::locale>()); | ||
|  | #endif
 | ||
|  |   output << value; | ||
|  |   output.exceptions(std::ios_base::failbit | std::ios_base::badbit); | ||
|  |   buf.try_resize(buf.size()); | ||
|  | } | ||
|  | 
 | ||
|  | // Formats an object of type T that has an overloaded ostream operator<<.
 | ||
|  | template <typename T, typename Char> | ||
|  | struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>> | ||
|  |     : private formatter<basic_string_view<Char>, Char> { | ||
|  |   using formatter<basic_string_view<Char>, Char>::parse; | ||
|  | 
 | ||
|  |   template <typename OutputIt> | ||
|  |   auto format(const T& value, basic_format_context<OutputIt, Char>& ctx) | ||
|  |       -> OutputIt { | ||
|  |     auto buffer = basic_memory_buffer<Char>(); | ||
|  |     format_value(buffer, value, ctx.locale()); | ||
|  |     return formatter<basic_string_view<Char>, Char>::format( | ||
|  |         {buffer.data(), buffer.size()}, ctx); | ||
|  |   } | ||
|  | 
 | ||
|  |   // DEPRECATED!
 | ||
|  |   template <typename OutputIt> | ||
|  |   auto format(const T& value, basic_printf_context<OutputIt, Char>& ctx) | ||
|  |       -> OutputIt { | ||
|  |     auto buffer = basic_memory_buffer<Char>(); | ||
|  |     format_value(buffer, value, ctx.locale()); | ||
|  |     return std::copy(buffer.begin(), buffer.end(), ctx.out()); | ||
|  |   } | ||
|  | }; | ||
|  | }  // namespace detail
 | ||
|  | 
 | ||
|  | FMT_MODULE_EXPORT | ||
|  | template <typename Char> | ||
|  | void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str, | ||
|  |             basic_format_args<buffer_context<type_identity_t<Char>>> args) { | ||
|  |   auto buffer = basic_memory_buffer<Char>(); | ||
|  |   detail::vformat_to(buffer, format_str, args); | ||
|  |   detail::write_buffer(os, buffer); | ||
|  | } | ||
|  | 
 | ||
|  | /**
 | ||
|  |   \rst | ||
|  |   Prints formatted data to the stream *os*. | ||
|  | 
 | ||
|  |   **Example**:: | ||
|  | 
 | ||
|  |     fmt::print(cerr, "Don't {}!", "panic"); | ||
|  |   \endrst | ||
|  |  */ | ||
|  | FMT_MODULE_EXPORT | ||
|  | template <typename S, typename... Args, | ||
|  |           typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>> | ||
|  | void print(std::basic_ostream<Char>& os, const S& format_str, Args&&... args) { | ||
|  |   vprint(os, to_string_view(format_str), | ||
|  |          fmt::make_args_checked<Args...>(format_str, args...)); | ||
|  | } | ||
|  | FMT_END_NAMESPACE | ||
|  | 
 | ||
|  | #endif  // FMT_OSTREAM_H_
 |